84 REVUE BHYOLOGTQUE 



In the female plant, which is usually more robust and shrubby 

 than the male, it was observed that although numerous archego- 

 nia arc produced on both sides of the axis, the sporogonia are as 

 a rule confined to one side or the other. Most of the fertile plants 

 examined showed on one side of the axis of each branch a scries 

 of sporogonia, the youngest being nearest the apex of the branch, 

 whilst the other side bore only unfertilised archegonia. Since a 

 single female plant may have as many as 10 branches, each with 

 about G sporogonia, a very large number of fruits may be produ- 

 ced; the greatest number observed on one plant was 54. 



In the mature capsule, the wall consists of a single layer of flat- 

 tened cells with yellowish-brown cell-walls ; at an earlier stage 

 these cells contain chloroplasts. The seta consists of a single series 

 of discoid cells, the walls of, which are of a deep brown colour. 

 The seta ends below in the dilated bulbous foot, the superficial 



w 



cells of which project as papillae. 



In a half-ripe capsule, the spore-tetrads are accompanied by 

 numerous sterile cells containing abundant starch-grains, and 

 there is a fairly regular layer of similar starch-bearing cells imme- 

 diately within \he single-layered wall of the capsule. These sterile 

 cells persist until the capsule is nearly mature, but the amount of 

 starch they contain becomes diminished during the ripening of 

 the spore. The ripe capsule becomes swollen, bursting through 

 the calyptra and usually becoming detached from the seta. This 

 is caused by the sterile cells, for it was found that in the fully- 

 grown capsule these cells are largely mucilaginous and become 

 swollen on the addition of water. The mucilage is derived from 

 the cell-walls and also apparently from the cell-contents. The 

 writers observations on living plants fully confirm the conclusion 

 drawn by Goebel (1) from the study of alcohol-material, i. e., that 

 the sterile cells serve a double function ; the starch they contain 

 is used up by the developing spores, and at a later stage, by beco- 

 ming mucilaginous and swelling,, they aid in the liberation of the 

 ripe spores. 



The writer hopes shortly to publish a detailed account of the 

 structure and development of this plant, specimens of which have 

 been kept under observation and grown in a small aquarium, 

 where they arc still flourishing. 



(1) Goehel, Ueber Function und Aulegung der Lebermooselateren. Flora, 

 1895, p. 8. 



